Bicyclo(3.3.0) octanones



18 Claims ABSTRACT OF THE DISCLOSURE The following compounds have beenprepared:

where A is -CX or CX R, X being halogen and R being an alkyl radical; Bbeing either halogen or alkyl. These compounds are formed bytransannular addition of polyhaloalkanes to 1,5-cyclooctadiene. Thecompounds of the invention have inter alia utility bactericides,fungicides, nematocides, insecticides, miticides, plasticizers and flameretardants.

This application is a division of Ser. No. 360,434, filed Apr. 16, 1964,now Patent No. 3,305,346, which is a continuation-in-part of Ser. No.254,575, filed Jan. 29, 1963, now abandoned.

This invention relates to derivatives of bicyclo[3.3.0 octane, and moreparticularly to such derivatives formed by transannular cycloadditionsto 1,5-cyclooctadiene.

It is known that cyclic alkenes, such as cyclohexene, form 1:1 additionproducts with various reactive compounds. For example, the reaction ofcyclohexane with carbon tetrachloride produces1-trichloromethyl-2-chlorocyclohexane. It would be expected, therefore,that compounds such as 1,5-cyclooctadiene would produce a mixture of 1:1and 1:2 adducts having similar structures.

It has been found, however, that 1,5-cyclooctadiene does not undergosimple addition reactions in many instances, and that the reaction of1,5-cyclooctadiene with polyhaloalkanes results in a transannularrearrangement to produce bicyclo[3.3.0]octane derivatives.

The bicyclo[3.3.0]ctane derivatives to which this invention relates andwhich are produced as a result of the reaction of 1,5-cyclooctadienewith polyhaloalkanes can be represented by the formula:

where A is CX or --CX R, X being halogen and R being an alkyl radical.The substituent B in the foregoing formula is either halogen orhydrogen.

Among the polyhaloalkanes which react with l,5-cyclo octadiene toproduce the aforesaid compounds are tetrahalomethanes, for example,carbon tetrahalides such as carbon tetrachloride and carbontetrabromide; trihalomethanes, including haloforms such as chloroformand nitcd States Patent 0 "ice bromoform; and alkyl haloforms such asalkyl chloroforms and alkyl bromoforms, the alkyl groups being typicallymethyl, ethyl, and propyl, although other alkyl haloforms, for example,those having alkyl groups of up to about 12 carbon atoms or more, mayalso be employed. Also included within the scope of the invention aremixed polyhaloalkanes in which the halogens are different, for example,such compounds as chlorotrifluoromethane, dichlorodifiuoromethane andtrichlorobromomethane.

The reaction of tetrahalomethanes with 1,5-cyclooctadiene producescompounds having the formula:

where X is halogen. As can be seen, one of the halogens from thetetrahalomethane is attached to the bicyclo- [3.3.0]octane nucleus inthe 6-position and a trihalomethyl radical is attached in the2-p0sition.

The product of the reaction utilizing a trihalomethane has the followingformula:

where X is halogen. In this instance, the hydrogen is attached to the6-position of the bicyclo[3.3.0]0ctane nucleus, and again atrihalomethyl group is attached at the 2-position.

When an alkyl trihalomethane, i.e., an alkyl haloform, is employed,however, the reaction results in products of the following formula:

where X is halogen and R is the alkyl radical. In this instance again ahalogen is attached to the 2-position and an alkyl dihalomethyl radicalis attached to the 6-position.

In each of the above instances, products of similar structure areobtained when mixed polyhalomethanes are employed, i.e.,polyhalomethanes in which different ihalogens are attached to the samecarbon. Thus, in the formulas set forth each X may represent a differenthalogen.

The reaction conditions used to produce the bicyclo [3.3.0]octanederivative from the polyhalornethane and 1,5 -cyclooctadiene are notcritical. For instance, no solvent is necessary, although one can beemployed if desired. Similarly, the ratio of reactants does not affectoperability of the reaction, although better yields are obtained if anexcess of the polyhalomethane is present. It is for this reason that asubstantial stoichiometric excess of the polyhalomethane is ordinarilyutilized; usually at least about 5 moles of polyhalomethane per mole of1,5-cyclooctadiene is employed.

In general, the reaction should be carried out utilizing conditions atwhich free radical-catalyzed additions take place. A catalyst as such isnot always necessary, but when a catalyst is not employed, elevatedtemperatures, C. or higher, and preferably to 250 C., should beemployed. Alternatively, a free radical-producing catalyst may beutilized. Among the catalysts which are often used are peroxides such asbenzoyl peroxide and di(tertiary butyl)peroxide, azo compounds such asazobis(isobutyronitrile), ultraviolet light, ferric chloride, andsimilar known free radical-producing catalysts. The amount of catalystis not critical, but the reaction is usually carried out using at leastabout 0.02 mole percent catalyst, based on 1,5-cyclopentadiene, althoughhigher or lower amounts can be employed if desired.

When a catalyst is present, the preferred temperature is that at whichthe catalyst yields free radicals at an appreciable rate. Thistemperature varies with the particular catalyst, for example, usingbenzoyl peroxide the temperature should be 70 C. or higher; withazobis(isobutyronitrile), 50 C. or higher; with di(tertiary butyl)peroxide, 120 C. or higher; while with ultraviolet light roomtemperature is often satisfactory.

In crop culture, the condition and quality of soil is of utmostimportance. Since nitrogen is necessary for plant growth, and since acommon pathway of nitrogen assimilation of plants is through roots inthe soil, adequate provision of nutrient nitrogen for plant growth mustbe made in the soil. Furthermore, it is necessary to provide favorablesoil environment around plant roots, such as freeing the soil fromsoil-dwelling nematodes, fungi and bacteria.

The provision of supplying nutrient nitrogen is one of the foremostagronomic problems. The nitrogen in the soil is found to occur primarilyin three forms: organic nitrogen, ammonium nitrogen, and nitratenitrogen, of which ammonium nitrogen and nitrate nitrogen are theprimary forms utilized by plants. This nitrogen is absorbed by plants insolution from the soil in the form of ammonium ions and nitrate ions.

The ammonium nitrogen in the soil is derived from bacterial conversionof organic nitrogen or from the added reduced nitrogen fertilizers, suchas anhydrous ammonia, aqueous ammonia, ammonium phosphate, ammoniumnitrate and ammonium sulfate. These ammonium compounds or inorganicreduced nitrogen compounds are readily soluble in water or aqueous soilmedium.

The nitrite and nitrate nitrogen in the soil are derived from theoxidation of ammonium nitrogen by soil bacteria, or by the addition ofinorganic nitrate fertilizers, such as ammonium nitrate, sodium nitrate,potassium nitrate and calcium nitrate. The process of oxidizing ammoniumnitrogen to nitrite ion is carried out by certain soil bacteria and isknown as nitrification. Microbacter organisms take over and convertnitrite to nitrate. The ionorganic nitrate compounds are also readilysoluble in water and other aqueous soil mediums. When so dissolved, thenitrate nitrogen largely exists as the nitrate 101'].

Because of the anionic nature of this ion, nitrate nitrogen is notadsorbed by soil colloids. Accordingly, the nitrate nitrogen is rapidlyleached by rainfall and irrigation, and readily lost from the feedingzone of the plants. Further, the nitrate nitrogen is reduced by manysoil bacteria, to gaseous volatile nitrogen oxides and to nitrogen gas.The latter process is known as denitrification and accounts for anadditional loss of large quantities of nitrate nitrogen from the soil.The yearly loss from leaching and denitrification amounts to from 20 to80 percent of the nitrate nitrogen found in the soil, whatever theanions source.

The tremendous losses of soil nitrogen initiated by the rapidnitrification of ammonium nitrogen, and the leaching and bacterialdenitrification of nitrate nitrogen have depleted many agriculturalsoils of the nitrogen reserves and nitrogen requirements for plantnutrition. In order to replenish the soil nitrogen, the agriculturalisthas resorted to the use of large amounts of synthetic nitratefertilizers and reduced nitrogen fertilizers. In many instances,multiple fertilizer treatments during the growing season have beenrequired to maintain the nitrogen requirements for plant growth. In thispracti the greater proportion of the employed fertilizers is in the formof reduced nitrogen fertilizers. By the expression reduced nitrogenfertilizers is meant fertilizers containing nitrogen in the reducedstate, and is inclusive of ammonium salts, ammonia; and alsowatersoluble organic compounds readily convertible in soil to ammonia orammonium ions, such as urea and cyanamide.

An object of this invention is the provision of a new and improvedmethod of suppressing the loss of ammonium nitrogen from soil. Anadditional object is the provision of a new and improved method forsuppressing the rapid nitrification of ammonium nitrogen in soil suchthat the product is not lost to the plant either through denitrificationor leaching. A further object is the provision of a method of improvingsoil environment of plant roots by the fumigation and disinfection ofsoil, infested with bacteria and fungi (microorganisms that do notenhance or promote plant growth) which attack plant roots.

By the practice of this invention, the nitrification of reduced orammonium nitrogen in the soil to nitrate nitrogen is suppressed, therebypreventing the rapid loss of ammonium nitrogen from the soil. Inaddition, by the practice of this invention, the control of soilinhabiting organisms such as bacteria and fungi may be achieved.

The provision of an effective amount of a novel trihalomethylenebicyclo[3.3.0]octane in the oil or growth medium, or amount sufiicientto suppress nitrification or control soil dwelling organisms(parasiticidal dosage) is essential for the practice of the presentinvention. In general, good results are obtained when the growth mediumis supplied with the bicyclooctanes in the amount of from 2 to 250 partsby volume per million parts by volume of medium. The preferred amount isconsidered to be from 5 to 50 parts by volume per million parts byvolume of soil. In field applications, the compounds may be distributedin the soil in the amount of at least 0.25 pound per acre, and throughsuch cross-section of the soil as to provide for the presence therein ofan effective concentration of the agent. It is usually preferred thatthe compounds be distributed to a depth of at least 2 inches below thesoil surface, and at a dosage of at least 0.5 pound per acre inch ofsoil. By dispersing very large dosages in growth media, a prolongedinhibition of nitrification may be obtained over a period of manymonths. Such application also provides more favorable growth media byfreeing the soil from the organisms attacking plants and plant roots andcontributing to adverse effects on plant growth. The concentration ofthe active compounds is eventually reduced to a minimum by decompositionin the soil.

In one embodiment of the present invention, the novel octanes aredistributed throughout the growth media prior to seeding ortransplanting the desired crop plant.

In another embodiment, the soil in the root zone of growing plants istreated with the novel octanes in an amount sufficient to inhibitnitrification and free the soil of bacteria and fungi but sublethal toplant growth. In such operations, the compounds should be supplied inthe soil in an amount no greater than about 250 parts by volume permillion parts by volume of the soil. By following such practice, noadverse effect is exerted by the compounds upon growth of seeds orplants. Oftentimes it is desirable to treat the soil adjacent to plants,and this procedure may be carried out conveniently in side-dressingoperations.

In a further embodiment, soil may be treated with the novel octanesfollowing harvest, or after fallowing to free soil of plant attackingorganisms, to prevent rapid loss of ammonium nitrogen and to build upthe ammonium nitrogen formed by conversion of organic nitrogencompounds. Such practice provides favorable growth media and conservesthe soil nitrogen for the following growing season.

In an additional embodiment, the soil is treated with the novel octanesin conjunction with the application of reduced nitrogen fertilizers. Thetreatment with the octanes may be carried out prior to, subsequent to,or simultaneously with the application of fertilizers. Such practiceprevents the rapid loss of the ammonium nitrogen added as fertilizer andthe ammonium nitrogen formed from the organic reduced nitrogen infertilizers by the action of soil bacteria. The administration to thesoil of the octane compounds in an ammonium nitrogen fertilizercomposition constitutes a preferred embodiment of the present invention.

The required amount of the compounds may be supplied to growth media infrom 1 to 50' gallons of organic solvent carrier, in from 1 to 27,000 ormore gallons of aqueous carrier or in from about to 2,000 pounds ofsolid carrier per acre treated.

The concentration of the compounds in compositions to be employed forthe treatment of growth media is not critical and may vary considerablyprovided the required dosage of elfective agent is supplied thereto. Theconcentration of the octanes may vary from 0.001 percent by volume to 95percent by volume of the composition, depending on whether thecomposition is a soil treating composition or a concentrate compositionand whether it is in the form of a solid or a liquid. In aqueous liquidtreating compositions, concentrations of from 0.001 percent to 10percent by volume of the octanes is considered the preferredcomposition. The concentration of the octanes in organic solvents may befrom 2 to 90' percent by volume. Solid compositions generally containfrom 5 to 50 percent by volume of the octane. Soil treating compositionsusually contain 0.004 percent to 10 percent by volume of the octanes. Incompositions to be employed as concentrates, the octane is oftentimespresent in a concentration of from 2.5 to 95 percent by volume.

Liquid compositions containing the desired amount of the compounds maybe prepared by dispersing the agents in one or more liquid carriers suchas Water and organic solvents with or Without the aid of a suitablesurfaceactive dispersing agent or emulsifying agent. Suitable organicsolvents include acetone, diisobutylketone, methanol, ethanol, isopropylalcohol, diethyl ether, toluene, methylene chloride, chlorobenzene andthe petroleum distillates. The preferred organic solvents are thosewhich are of such volatility that they leave little permanent residuesin the soil. When the solutions of active compounds in organic solventsare to be further diluted to produce aqueous dispersions, the preferredsolvents include acetone and the alcohols. When the liquid carrier isentirely organic in nature, particularly desirable carriers are thepetroleum distillates boiling almost entirely under 400 F. atatmospheric pressure and having a flash point above about 80 F.

Dispersing and emulsifying agents which may be employed in liquidcompositions include condensation products of 'alkylene oxides withphenols and organic acids, alkyl aryl sulfonates, polyoxyalkylenederivatives of sorbitan esters, complex ether alcohols, mahogany soapsand the like. The surface-active agents are generally employed in theamount of from 1 to percent by weight of the combined Weight of octanesand surface-active agent.

Solid compositions containing the active octane may be prepared bydispersing the compounds in finely divided inert solid carriers such astalc, chalk, gypsum, vermiculite, bentonite and the like, fullers earth,attapulgite and other clays, various solid detergent dispersing agentsand solid fertilizer compositions. In preparing such compositions, thecarrier is mechanically admixed with the octane liquid or wet with asolution thereof in a volatile organic solvent. Depending upon theproportions of ingredients, these compositions may be employed withoutfurther modifications or be considered concentrates and subsequentlyfurther diluted with solid surface-active dispersing agent, talc, chalk,gypsum or the like obtain the desired treating composition. Furthermore,such concentrate compositions may be dispersed in Water with or withoutadded dispersing agent or agents to prepared aqueous soil treatingcompositions.

Soil treating compositions may be prepared by dispersing the octanes infertilizers such as ammonium fertilizer or organic nitrogen fertilizer.The resulting fertilizer compositions may be employed as such or may bemodified such as by dilution with additional nitrogen fertilizer or withinert solid carrier to obtain a composition containing the desiredamount of active agent for treatment of soil. Further, an aqueousdispersion of the octanes fertilizer composition may be prepared andadministered to the growth medium. Fertilizer compositions comprisingthe octanes in intimate admixture with ammonium fertilizers constitutepreferred embodiments of the present invention. In fertilizercompositions comprising a reduced nitrogen fertilizer, it is desirablethat the octanes be present in an amount of at least 0.5 percent byweight based on the nitrogen present in the fertilizer as reducednitrogen. Thus, when a fertilizer composition contains both reducednitrogen and other forms of nitrogen such as in the case of ammoniumnit-rate fertilizer compositions, the amount of the octanes is based onthe weight of the nitrogen present in the ammonium component.

In operations carried out in accordance with the present invention, thesoil may be impregnated in any convenient fashion with the activecompounds or a composition containing these agents. For examples, thesemodified or unmodified compositions may be simply mechanically mixedwith the soil, applied to the surface of soil and thereafter dragged ordisced into the soil to a desired depth; transported into the soil witha liquid carrier such as by injection, spraying or irrigation. When thedistribution is carried out 'by introducing the compounds in the wateremployed to irrigate the soil, the amount of water is varied inaccordance with the moisture content of the soil in order to obtain adistribution of the compounds to the desired depth. The compounds may bereadily and conveniently distributed to a depth of from two to four feet'by irrigation methods. The preferred methods embrace procedures usingany of these steps wherein the compounds are distributedin the soilsubstantially simultaneously with a reduced nitrogen fertilizer.

The following examples illustrate the invention but are not to beconstrued as limiting.

Example 1.Reaction of 1,5-cyclooctadiene and carbon tetrachloride Amixture of 325 grams of 1,5-cyclcoctadiene, 21.8 grams of benzoylperoxide and 3 liters of carbon tetrachloride was refiuxed for two days,an additional 14.5 grams of 'benzoyl peroxide was added and the mixturewas refluxed for an additional 1.5 days. Most of the excess carbontetrachloride was then removed by distillation, the residue wasdissolved in ethyl ether and washed with aqueous sodium bicarbonate.After the ether was evaporated off, the remaining mixture was distilledand the main fraction obtained was redistilled, whereby there wereobtained 283 grams of a fraction boiling at 87 C. at 0.10 millimeterpressure to 90 C. at 0.15 millimeter pressure. This product wasidentified as pure 2-trichloromethyl-6-chlorobicyclo[3.3.0] octane,having the structure:

C Cla Analysis.-(Calculated for C H Cl Calculated, percent: C, 41.25; H,4.62; Cl, 54.13. Found, percent: C, 41.27; H, 4.89; CI, 53.84.

In addition to chemical analysis, the product was identified by gaschromatographic analysis, which showed essentially one compound; byinfrared analysis which showed only two bands in the 3.4 micron regionand no bands at wavelengths lower than 3.40 microns; by proton magneticresonance analysis; and by its chemical behavior in characterizingreactions.

EXAMPLE 2 The same product as in Example 1 was produced by refluxing amixture of 27 grams of 1,5-cyclooctadiene, 125 milliliters of carbontetrachloride, 75 milliliters of isopropyl alcohol and 1 gram of ferricchloride hexahydrate for 36 hours. After washing the mixture with waterand evaporating the organic layer, 54 grams of a liquid were obtainedwhich was distilled, whereby there was obtained 48.4 grams of2-trichloromethyl-6-chlorobicyclo [3.3.0]octane.

Example 3.Reaction of 1,5-cyclooctadiene with chloroform A mixture of108 grams of 1,5-cycloctadiene, 4.9 grams of benzoyl peroxide and 1liter of chloroform was refluxed for days with additions on consecutivedays of four 2.4 gram portions of benzoyl peroxide, thus making thetotal amount of peroxide used 14.5 grams. Distillation of the reactionmixture yielded 74 grams of a liquid which was redistilled severaltimes. There was obtained 30.0 grams of a fraction boiling at 110 C. to111 C. at 9 millimeters pressure, identified as pure 2-trichloromethylbicyclo[3.3.0]octane having the structure:

CCl3

It was identified by its infrared spectrum, its nuclear magneticresonance spectrum and its gas chromatogram, as well as by chemicalanalysis.

Analysis.(Calculated for C H Cl Calculated, percent: C, 47.49; H, 5.75;Cl, 46.74. Found, percent: C, 47.19; H, 5.42; Cl, 46.45.

Example 4.Reaction of 1,5-cyclo0ctadiene with bromotrichloromethane Amixture of 27 grams of 1,5-cyclooctadiene, 3 grams of benzoyl peroxideand 148.5 grams of bromotrichloromethane was heated slowly to 75 C.whereupon an exothermic reaction occurred and the temperature rose to114 C. The mixture was maintained at 80 to 90 C. for 24 hours, afterwhich the excess bromotrichloromethane was distilled off and the residuedistilled. There was obtained 54 grams of crude product comprising amixture of 2 trichloromethyl 6-bromo'bicyclo[3.3.0] octane and 2bromodichloromethyl 6-chlorobicyclo[3.3.0]octane, having the followingstructures:

and

CC12B I Example 5.-Reaction of 1,5-cyolooctadiene with carbontetrabromide A mixture of 22.4 grams of 1,5-cyclooctadiene and 275.4grams of carbon tetrabromide was heated to 75 C.

and stirred and irradiated at this temperature for 2 days underultraviolet light from a sunlamp. After the excess carbon tetrabromidehad been removed, there remained a residue comprising crude2-tribromomethyl-6-bromobicyclo-[3.3.0]octane, which tended to decomposeupon further distillation.

Example 6.--Reaction of 1,5-cyclooctadiene with methyl chloroform Amixture of 108 grams of 1,5-cyclooctadiene, 4.9 grams of benzoylperoxide and 700 milliliters of methyl chloroform was refluxed at 71 C.for 5 days, with additions of four 2.4 gram portions of benzoyl peroxideon successive days starting with the second day. The rem-oval ofunreacted methyl chloroform and cyclooctadiene and distillation of theresidue yielded a liquid which, after Washing with aqueous sodiumbicarbonate solution, was redistilled. There was obtained 24.4 grams ofcrude product comprising 2-(1,l-dichloroethyl)-6-chlorobicyclo[3.3.0]octane of the structure:

It has been further found that the foregoing products can be hydrolyzedto produce compounds in which the trihalomethyl group is converted to adihailomethylene group. Such dihalomethylenebicyclo[3.3.01octanes havethe formula:

where X is halogen. In addition, the hydrolysi produces thecorresponding acid in which the trihalomethyl substituent is replaced bya car boxyl radical. The hydrolysis is particularly easily accomplishedin the case of the products obtained from trihalomethane. The hydrolysisreaction requires the presence of a strong acid, and is usually carriedout by reacting the bicyclo[3.3.0]octane derivative with an aqueoussolution of the acid. Among the acids which are thus employed areprosphoric acid and sulfuric acid, which are preferred, and nitric acid,which due to its oxidizing properties is less desirable since it maytend to engage in side reactions, thus reducing the yield of the desiredproduct. The example below illustrates the ease and efficiency withwhich the dihalomethylene derivatives and acids are produced.

Example 7.-Hydrolysis of 2-trichloroniethylbicyclo [3.3.0]octane Amixture of 111 grams of 2-trichloromethyl-bicyclo [3.3.0]octane,produced as in Example 3 above, and 500 milliliters of percentphosphoric acid was refluxed for 24 hours. The mixture was cooled,diluted with water, extracted with ether and the resulting extractseparated into acidic and neutral fractions with aqueous sodiumbicarbonate. The neutral fraction was distilled and gave 29.5 grams of afraction boiling at 107 C. to 119 C. at 15 millimeters pressure. Afterredistillation this fraction was identified as2-dichloromethylenebicyclo[3.3.0]octane of the structure:

Identification was by gas chromatographic, infrared, and chemicalanalysis:

Analysis(Calculated for C H Cl Calculated, percent: C, 56.56; H, 6.33;C11. 37.11. Found, percent: C, 56.76; H, 6.42; Cl, 35.26.

Distillation of the acid fraction gave 29.4 grams ofexo,cisbicyclo[3.3.0]octane-Z-carboxylic acid of the structure:

if (ll-H It had a boiling point of 89 C. at 0.1 millimeter pressure.

Analysis.(Calculated for C H O Calculated, percent: C, 70.10; H, 9.15.Found, percent: C, 70.61; H, 9.00.

In these and other tests, various products corresponding to the formulasdisclosed above were produced using varying reaction conditions andcatalysts, and with reactants of different types within the classdescribed.

In addition to providing an advantageous route to the correspondingacids and the dihalomethylene derivatives, as illustrated above, thecompounds of this invention can be used for other purposes. For example,they are useful as plasticizers for resinous compositions, beinghigh-boiling liquids of high halogen content. When used in this manner,they aid in imparting fire retardancy in addition to their plasticizingproperties. They are also valuable chemical intermediates and can beused to produce insecticidal and biologically active materials, forexample, through reduction of dehydrohallogenation reactions. Thedihalomethylene compounds themselves are excellent pesticides. Forinstance, 2-dichloromethylenebicyclo[3.3.0] octane is an effectivefungicide and miticide. In one test illustrating its utility in thisregard, concentrations of 2-dichloromethylenebicyclo[3.3.0] octane aslow as .01 percent prevented germination of Monilia fructicola, thecasual organism of brown rot of stone fruit. It has also been showneffective against other fungi such as Alternaria solani and ag instmites such as the spotted spider mite (Tetranychus telarius).

Example 8 One tenth milliliter of2-trichloromethyl-6-chlorobicyclo[-3.3.0]octane was employed as thecandidate bactericide against a pure culture of Nitrosomonas europaea, abacterium known to oxidize ammonium ion to the nitrite ion.

The culture medium was prepared as follows:

Aliquots of 100 ml. of the foregoing prepared medium were placed inflasks, sealed, inoculated equally with the N. europaea bacterium, and aminim-um time of about 6 days permitted to elapse to permit relativelyprofuse development of the bacterium. The candidate bactericides of 0.1m1. volume was then added to the flasks. The in oculated flasks wereincubated at 28 C. on a rotary shaker for six days, and then wereanalyzed quantitatively for nitrite content.

In a check operation, other flasks were prepared in the identicalmanner, omitting inoculation with a bactericide.

Nitrite ion is the particular product of the oxidation of ammoniumnitrogen by N. europaea. Nitrite ion was determined using theGriess-llsovay reagent, and a Klett Summerson colorimeter.

Percent inhibition of nitrite production was calculated as follows:

Nitrite produced in presence of candidate bactericide Nitrite producedin absence of candidate bactericide The results obtained in testing2-trichloromethyl-6- chlorobicyclo[3.3.01octane indicated 94% inhibitionof ammonium nitrogen oxidation to nitrite. With the check flasks, therewas no inhibition of ammonium ion oxidation.

Workers in the microbiological art have long experienced difiiculty inisolation of nitrifying bacteria, particularly in the isolation of thegenus Nitrosomonas in pure culture. The availability of the bacterium inpure form greatly aids in conducting the measurements employed in thecurrent determinations. The pure culture of Nizrosomonas europaeaemployed herein, were prepared according to the teaching of Lewis andPrarner, reported at J. of Bacteriology, 76, pp. 524-528 (1958).

According to the provisions of the patent statutes, there are describedabove the invention and what are now considered to be its bestembodiments. However, within the scope of the appended claims, it is tobe understood that the invention may be practiced otherwise than asspecifically described.

What is claimed is:

1. A compound of the formula:

Percent inhibition= X in which substituent A is a radical selected fromthe class consisting of CX and CX 'R, wherein X is chlorine or bromineand R is alkyl, and substituent B is selected from the class consistingof chlorine or bromine and hydrogen.

2. The compound of claim 1 in which X is chlorine. 3. A compound of theformula:

where X is chlorine or bromine.

4. The compound of claim 3 in which X is chlorine. 5. A compound of theformula:

where X is chlorine or bromine.

6. The compound of claim 5 in which X is chlorine. 7. A compound of theformula:

where X is chlorine or bromine and 'R is al-kyl.

8. The compound of claim 7 in which X is chlorine and R is methyl.

9. The method of producing a bicyclo[3.3.0]octane derivatile whichcomprises reacting 1,5-cyclooctadiene with a polyhaloalkane of theformula RCX where X is chlorine or bromine and R is selected from theclass consisting of chlorine, bromine, hydrogen and alkyl radicals, thereaction being carried out in the presence of a free-radical producingcatalyst at a temperature at which the said catalyst yields freeradicals at an appreciable rate.

10. The method of claim 9 in which a stoichiometric excess of saidpolyhaloalkane is present.

11. The method of producing a bicyclo[3.3.0]octane derivative whichcomprises reacting 1,5-cyclooctadiene with a polyhaloalkane of theformula RCX where X is chlorine or bromine and R is selected from theclass consisting of chlorine, bromine, hydrogen and alkyl radicals, thereaction being carried out in the absence of a catalyst at a temperatureof at least about 100 C.

12. The method of claim 11 in which a stoichiometric excess of saidpolyhaloalkane is present.

13. The method of claim 9 which comprises reacting 1,5-cyclooctadienewith a haloform, wherein the halogen atoms are chlorine or bromine, thereaction being carried out in the presence of a free radical producingcatalyst at a temperature at which the said catalyst yields freeradicals at an appreciable rate.

14. The method of claim 11 which comprises reacting 1,5-cyclooctadienewith a haloform, wherein the halogen atoms are chlorine or bromine, thereaction being carried out in the absence of a catalyst at a temperatureof at least about 100 C.

15. The method of claim 9 which comprises reacting 1,5-cyclooctadienewith an alkyl haloform, wherein the halogen atoms are chlorine orbromine, the reaction being carried out in the presence of a freeradical producing 12 catalyst at a temperature at which the saidcatalyst yields free radicals at an appreciable rate.

16. The method of claim 11 which comprises reacting 1,5-cyclooctadienewith an alkyl haloform, wherein the halogen atoms are chlorine orbromine, the reaction being carried out in the absence of a catalyst ata temperature of at least about 100 C.

17. The method of claim 9 which comprises reacting 1,5-cyclooctadieneWith a carbon tetrahalide, the reaction being carried out in thepresence of a free-radical producing catalyst at a temperature at whichthe said catalyst yields free radicals at an appreciable rate.

18. The method of claim 11 which comprises reacting 1,5-cyclooctadienewith a carbon tetrahalide, the reaction being carried out in the absenceof a catalyst at a temperature of at least about 100 C.

References Cited FOREIGN PATENTS 1,036,847 l/l959 Germany.

OTHER REFERENCES Mair et al.: Chem. Abst., vol. 52, col. 10555d (1958).

Hanna et al.: J. Am. Chem. Soc., vol. 82, pp. 6342 to 6347 (1960).

LEON ZITVER, Primary Examiner.

M. JACOB, Assistant Examiner.

US. Cl. X.R.

